This invention presents a sill assembly with an adjustable threshold to be installed onto the floor of an entry-door. A sill assembly with a threshold, either fixed or adjustable, is usually used with door jambs together to frame an entry-door unit. An entry-door is also commonly equipped at the bottom with a weatherstrip, for instance, a door sweep. When an entry-door is closed, the sill's threshold is in the same plane with the door's weather-strip, is flushed with it, and pressed against it; therefore, the sill assembly with a threshold helps prevent exterior water, moisture, and air from entering a home.
Prior arts include a variety of sill assemblies which have been designed to be installed as thresholds for doorway. The sill assemblies of prior arts can be classified into two categories: fixed sills and adjustable sills. Both categories of sills feature some generally recognizable parts: a unitary housing which holds all inner parts, two or multiple supporting legs, and a raised and flat platform against which an entry-door's weather-strip, such as a door sweep, is pressed when a door is closed.
In the first category, fixed sills have an elongated unitary body with or without a removable threshold cap. They are usually made of solid woods, or extruded metals, for examples, aluminum or brass. Sills in this category are fixed because the threshold sections are uniformly fixed and connected to the base, and cannot be adjusted by any means. Because sills are fixed, they have consistent height and shape from one end to the other end.
In the second category, adjustable sills also have an elongated unitary body, but usually with an adjustable threshold cap. Examples of adjustable sills include prior arts U.S. Pat. Nos. 5,426,894 and 5,517,788 and 5,638,641 and 6,345,477. The adjustable threshold cap and its housing can be made of extruded aluminum or routed hardwood. An adjustable sill is usually adjusted manually by hand to achieve a desired uniform height of the cap, so that the cap can be properly pressed against a weatherstrip which is installed at the entry-door's bottom. The said cap may have multiple screw-holes, punched and countersunk with equal spacing along the cap's longitudinal axis, so that adjustment screws can be fastened into the housing. An installer can lower the height by turning the adjustment screws clockwise, one-by-one in sequence. Conversely, an installer can raise the height by turning the adjustment screws counter-clockwise, one-by-one in sequence. In general, the adjustable sills of prior arts have adjustment screws which are visible and accessible from the threshold cap's top, as presented by U.S. Pat. Nos. 5,179,804 and 5,517,788 and 5,524,391. In the example of U.S. Pat. No. 6,345,477, the threshold cap's screw-holes are covered by plastic plugs.
In adjustable sills of prior arts, some lack water-proof seals, but others have exposed water-proof seals. Examples of adjustable sills that lack water-proof seals include U.S. Pat. Nos. 4,352,258 and 6,345,477. In these two prior-art examples, the absence of a water-proof seal may allow water, moisture, and air to penetrate through the sill into a home. Over time, the inner adjustment parts may deteriorate due to external weatherization.
Examples of adjustable sills that have water-proof seals are: U.S. Pat. Nos. 5,179,804 and 5,230,181 and 5,426,894 and 5,517,788 and 5,524,391 and 5,638,641 and 7,472,516. These prior inventions' water-proof seals may be made be of flexible vinyl, plastic, or foam weather-strip, all for preventing water, moisture, and air from passing through the sill into a home. Nonetheless, these prior inventions' water-proof seals are exposed and visible. Such exposed, visible seals can deteriorate over time due to weatherization and normal wear-and-tear. Finally, these exposed, visible seals reduce the aesthetic value of a uniform look and shape in the sill assemblies.
This invention presents a new sill assembly with an adjustable threshold, which is to be installed onto the floor of a doorway. This sill, being used together with a weather-strip, such as a door shoe, or vinyl sealing strip, is to block water, moisture, and air from entering a home.